Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752439Ab2JHFUs (ORCPT ); Mon, 8 Oct 2012 01:20:48 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:24607 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751600Ab2JHFUo (ORCPT ); Mon, 8 Oct 2012 01:20:44 -0400 X-IronPort-AV: E=Sophos;i="4.80,551,1344182400"; d="scan'208";a="5957679" Message-ID: <507263F8.9040200@cn.fujitsu.com> Date: Mon, 08 Oct 2012 13:26:16 +0800 From: Wen Congyang User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.9) Gecko/20100413 Fedora/3.0.4-2.fc13 Thunderbird/3.0.4 MIME-Version: 1.0 To: KOSAKI Motohiro CC: Yasuaki Ishimatsu , x86@kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-acpi@vger.kernel.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, linux-ia64@vger.kernel.org, cmetcalf@tilera.com, sparclinux@vger.kernel.org, rientjes@google.com, liuj97@gmail.com, len.brown@intel.com, cl@linux.com, minchan.kim@gmail.com, akpm@linux-foundation.org Subject: Re: [PATCH 0/10] memory-hotplug: hot-remove physical memory References: <506E43E0.70507@jp.fujitsu.com> In-Reply-To: X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2012/10/08 13:20:35, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2012/10/08 13:20:36, Serialize complete at 2012/10/08 13:20:36 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1477 Lines: 30 At 10/06/2012 03:06 AM, KOSAKI Motohiro Wrote: >> Known problems: >> 1. memory can't be offlined when CONFIG_MEMCG is selected. >> For example: there is a memory device on node 1. The address range >> is [1G, 1.5G). You will find 4 new directories memory8, memory9, memory10, >> and memory11 under the directory /sys/devices/system/memory/. >> If CONFIG_MEMCG is selected, we will allocate memory to store page cgroup >> when we online pages. When we online memory8, the memory stored page cgroup >> is not provided by this memory device. But when we online memory9, the memory >> stored page cgroup may be provided by memory8. So we can't offline memory8 >> now. We should offline the memory in the reversed order. >> When the memory device is hotremoved, we will auto offline memory provided >> by this memory device. But we don't know which memory is onlined first, so >> offlining memory may fail. In such case, you should offline the memory by >> hand before hotremoving the memory device. > > Just iterate twice. 1st iterate: offline every non primary memory > block. 2nd iterate: > offline primary (i.e. first added) memory block. It may work. > OK, I will try it. Thanks Wen Congyang -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/